Esempio n. 1
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// Set sets session variables.
// Privileges: None.
//   Notes: postgres/mysql do not require privileges for session variables (some exceptions).
func (p *planner) Set(n *parser.Set) (planNode, error) {
	if n.Name == nil {
		// A client has sent the reserved internal syntax SET ROW ...
		// Reject it.
		return nil, errors.New("invalid statement: SET ROW")
	}

	// By using VarName.String() here any variables that are keywords will
	// be double quoted.
	name := strings.ToUpper(n.Name.String())
	typedValues := make([]parser.TypedExpr, len(n.Values))
	for i, expr := range n.Values {
		typedValue, err := parser.TypeCheck(expr, nil, parser.TypeString)
		if err != nil {
			return nil, err
		}
		typedValues[i] = typedValue
	}
	switch name {
	case `DATABASE`:
		dbName, err := p.getStringVal(name, typedValues)
		if err != nil {
			return nil, err
		}
		if len(dbName) != 0 {
			// Verify database descriptor exists.
			if _, err := p.mustGetDatabaseDesc(dbName); err != nil {
				return nil, err
			}
		}
		p.session.Database = dbName

	case `SYNTAX`:
		s, err := p.getStringVal(name, typedValues)
		if err != nil {
			return nil, err
		}
		switch sqlbase.NormalizeName(parser.Name(s)) {
		case sqlbase.ReNormalizeName(parser.Modern.String()):
			p.session.Syntax = int32(parser.Modern)
		case sqlbase.ReNormalizeName(parser.Traditional.String()):
			p.session.Syntax = int32(parser.Traditional)
		default:
			return nil, fmt.Errorf("%s: \"%s\" is not in (%q, %q)", name, s, parser.Modern, parser.Traditional)
		}

	case `EXTRA_FLOAT_DIGITS`:
		// These settings are sent by the JDBC driver but we silently ignore them.

	default:
		return nil, fmt.Errorf("unknown variable: %q", name)
	}
	return &emptyNode{}, nil
}
Esempio n. 2
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// upsertExprsAndIndex returns the upsert conflict index and the (possibly
// synthetic) SET expressions used when a row conflicts.
func upsertExprsAndIndex(
	tableDesc *sqlbase.TableDescriptor,
	onConflict parser.OnConflict,
	insertCols []sqlbase.ColumnDescriptor,
) (parser.UpdateExprs, *sqlbase.IndexDescriptor, error) {
	if onConflict.IsUpsertAlias() {
		// The UPSERT syntactic sugar is the same as the longhand specifying the
		// primary index as the conflict index and SET expressions for the columns
		// in insertCols minus any columns in the conflict index. Example:
		// `UPSERT INTO abc VALUES (1, 2, 3)` is syntactic sugar for
		// `INSERT INTO abc VALUES (1, 2, 3) ON CONFLICT a DO UPDATE SET b = 2, c = 3`.
		conflictIndex := &tableDesc.PrimaryIndex
		indexColSet := make(map[sqlbase.ColumnID]struct{}, len(conflictIndex.ColumnIDs))
		for _, colID := range conflictIndex.ColumnIDs {
			indexColSet[colID] = struct{}{}
		}
		updateExprs := make(parser.UpdateExprs, 0, len(insertCols))
		for _, c := range insertCols {
			if _, ok := indexColSet[c.ID]; !ok {
				names := parser.UnresolvedNames{
					parser.UnresolvedName{parser.Name(c.Name)},
				}
				expr := &parser.ColumnItem{
					TableName:  upsertExcludedTable,
					ColumnName: parser.Name(c.Name),
				}
				updateExprs = append(updateExprs, &parser.UpdateExpr{Names: names, Expr: expr})
			}
		}
		return updateExprs, conflictIndex, nil
	}

	indexMatch := func(index sqlbase.IndexDescriptor) bool {
		if !index.Unique {
			return false
		}
		if len(index.ColumnNames) != len(onConflict.Columns) {
			return false
		}
		for i, colName := range index.ColumnNames {
			if sqlbase.ReNormalizeName(colName) != sqlbase.NormalizeName(onConflict.Columns[i]) {
				return false
			}
		}
		return true
	}

	if indexMatch(tableDesc.PrimaryIndex) {
		return onConflict.Exprs, &tableDesc.PrimaryIndex, nil
	}
	for _, index := range tableDesc.Indexes {
		if indexMatch(index) {
			return onConflict.Exprs, &index, nil
		}
	}
	return nil, nil, fmt.Errorf("there is no unique or exclusion constraint matching the ON CONFLICT specification")
}
Esempio n. 3
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// Initializes a scanNode with a tableName. Returns the table or index name that can be used for
// fully-qualified columns if an alias is not specified.
func (n *scanNode) initTable(
	p *planner,
	tableName *parser.TableName,
	indexHints *parser.IndexHints,
	scanVisibility scanVisibility,
) error {
	descFunc := p.getTableLease
	if p.asOf {
		// AS OF SYSTEM TIME queries need to fetch the table descriptor at the
		// specified time, and never lease anything. The proto transaction already
		// has its timestamps set correctly so mustGetTableDesc will fetch with the
		// correct timestamp.
		descFunc = p.mustGetTableDesc
	}
	desc, err := descFunc(tableName)
	if err != nil {
		return err
	}
	n.desc = *desc

	if err := p.checkPrivilege(&n.desc, privilege.SELECT); err != nil {
		return err
	}

	if indexHints != nil && indexHints.Index != "" {
		indexName := sqlbase.NormalizeName(indexHints.Index)
		if indexName == sqlbase.ReNormalizeName(n.desc.PrimaryIndex.Name) {
			n.specifiedIndex = &n.desc.PrimaryIndex
		} else {
			for i := range n.desc.Indexes {
				if indexName == sqlbase.ReNormalizeName(n.desc.Indexes[i].Name) {
					n.specifiedIndex = &n.desc.Indexes[i]
					break
				}
			}
			if n.specifiedIndex == nil {
				return fmt.Errorf("index \"%s\" not found", indexName)
			}
		}
	}
	n.noIndexJoin = (indexHints != nil && indexHints.NoIndexJoin)
	n.initDescDefaults(scanVisibility)
	return nil
}
Esempio n. 4
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// findUnaliasedColumn looks up the column specified by a VarName, not
// taking column renames into account (but table renames will be taken
// into account). That is, given a table "blah" with single column "y",
// findUnaliasedColumn("y") returns a valid index even in the context
// of:
//     SELECT * FROM blah as foo(x)
// If the VarName specifies a table name, only columns that have that
// name as their source alias are considered. If the VarName does not
// specify a table name, all columns in the data source are
// considered.  If no column is found, invalidColIdx is returned with
// no error.
func (p *planDataSource) findUnaliasedColumn(
	c *parser.ColumnItem,
) (colIdx int, err error) {
	colName := sqlbase.NormalizeName(c.ColumnName)
	tableName := sqlbase.NormalizeTableName(c.TableName)

	if tableName.Table() != "" {
		tn, err := p.info.checkDatabaseName(tableName)
		if err != nil {
			return invalidColIdx, nil
		}
		tableName = tn
	}

	colIdx = invalidColIdx
	planColumns := p.plan.Columns()

	selCol := func(colIdx int, idx int) (int, error) {
		col := planColumns[idx]
		if sqlbase.ReNormalizeName(col.Name) == colName {
			if colIdx != invalidColIdx {
				return invalidColIdx, fmt.Errorf("column reference \"%s\" is ambiguous", parser.AsString(c))
			}
			colIdx = idx
		}
		return colIdx, nil
	}

	if tableName.Table() == "" {
		for idx := 0; idx < len(p.info.sourceColumns); idx++ {
			colIdx, err = selCol(colIdx, idx)
			if err != nil {
				return colIdx, err
			}
		}
	} else {
		colRange, ok := p.info.sourceAliases[tableName]
		if !ok {
			// A table name is specified, but there is no column with this
			// table name.
			return invalidColIdx, nil
		}
		for _, idx := range colRange {
			colIdx, err = selCol(colIdx, idx)
			if err != nil {
				return colIdx, err
			}
		}
	}

	return colIdx, nil
}
Esempio n. 5
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func makeColIDtoRowIndex(row planNode, desc *sqlbase.TableDescriptor) (
	map[sqlbase.ColumnID]int, error,
) {
	columns := row.Columns()
	colIDtoRowIndex := make(map[sqlbase.ColumnID]int, len(columns))
	for i, column := range columns {
		s, idx, err := desc.FindColumnByNormalizedName(sqlbase.ReNormalizeName(column.Name))
		if err != nil {
			return nil, err
		}
		switch s {
		case sqlbase.DescriptorActive:
			colIDtoRowIndex[desc.Columns[idx].ID] = i
		case sqlbase.DescriptorIncomplete:
			colIDtoRowIndex[desc.Mutations[idx].GetColumn().ID] = i
		default:
			panic("unreachable")
		}
	}
	return colIDtoRowIndex, nil
}
Esempio n. 6
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func nameMatchesLease(lease *LeaseState, dbID sqlbase.ID, tableName string) bool {
	return lease.ParentID == dbID &&
		sqlbase.ReNormalizeName(lease.Name) == sqlbase.ReNormalizeName(tableName)
}
Esempio n. 7
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func makeTableNameCacheKey(dbID sqlbase.ID, tableName string) tableNameCacheKey {
	return tableNameCacheKey{dbID, sqlbase.ReNormalizeName(tableName)}
}
Esempio n. 8
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// findColumn looks up the column specified by a VarName. The normalized VarName
// is returned.
func (sources multiSourceInfo) findColumn(
	c *parser.ColumnItem,
) (info *dataSourceInfo, colIdx int, err error) {
	if len(c.Selector) > 0 {
		return nil, invalidColIdx, util.UnimplementedWithIssueErrorf(8318, "compound types not supported yet: %q", c)
	}

	colName := sqlbase.NormalizeName(c.ColumnName)
	var tableName parser.TableName
	if c.TableName.Table() != "" {
		tableName = sqlbase.NormalizeTableName(c.TableName)

		tn, err := sources.checkDatabaseName(tableName)
		if err != nil {
			return nil, invalidColIdx, err
		}
		tableName = tn

		// Propagate the discovered database name back to the original VarName.
		// (to clarify the output of e.g. EXPLAIN)
		c.TableName.DatabaseName = tableName.DatabaseName
	}

	colIdx = invalidColIdx
	for _, src := range sources {
		findCol := func(src, info *dataSourceInfo, colIdx int, idx int) (*dataSourceInfo, int, error) {
			col := src.sourceColumns[idx]
			if sqlbase.ReNormalizeName(col.Name) == colName {
				if colIdx != invalidColIdx {
					return nil, invalidColIdx, fmt.Errorf("column reference %q is ambiguous", c)
				}
				info = src
				colIdx = idx
			}
			return info, colIdx, nil
		}

		if tableName.Table() == "" {
			for idx := 0; idx < len(src.sourceColumns); idx++ {
				info, colIdx, err = findCol(src, info, colIdx, idx)
				if err != nil {
					return info, colIdx, err
				}
			}
		} else {
			colRange, ok := src.sourceAliases[tableName]
			if !ok {
				// The data source "src" has no column for table tableName.
				// Try again with the net one.
				continue
			}
			for _, idx := range colRange {
				info, colIdx, err = findCol(src, info, colIdx, idx)
				if err != nil {
					return info, colIdx, err
				}
			}
		}
	}

	if colIdx == invalidColIdx {
		return nil, invalidColIdx, fmt.Errorf("column name %q not found", c)
	}

	return info, colIdx, nil
}
Esempio n. 9
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// orderBy constructs a sortNode based on the ORDER BY clause.
//
// In the general case (SELECT/UNION/VALUES), we can sort by a column index or a
// column name.
//
// However, for a SELECT, we can also sort by the pre-alias column name (SELECT
// a AS b ORDER BY b) as well as expressions (SELECT a, b, ORDER BY a+b). In
// this case, construction of the sortNode might adjust the number of render
// targets in the selectNode if any ordering expressions are specified.
//
// TODO(dan): SQL also allows sorting a VALUES or UNION by an expression.
// Support this. It will reduce some of the special casing below, but requires a
// generalization of how to add derived columns to a SelectStatement.
func (p *planner) orderBy(orderBy parser.OrderBy, n planNode) (*sortNode, error) {
	if orderBy == nil {
		return nil, nil
	}

	// We grab a copy of columns here because we might add new render targets
	// below. This is the set of columns requested by the query.
	columns := n.Columns()
	numOriginalCols := len(columns)
	if s, ok := n.(*selectNode); ok {
		numOriginalCols = s.numOriginalCols
	}
	var ordering sqlbase.ColumnOrdering

	for _, o := range orderBy {
		index := -1

		// Unwrap parenthesized expressions like "((a))" to "a".
		expr := parser.StripParens(o.Expr)

		if vBase, ok := expr.(parser.VarName); ok {
			v, err := vBase.NormalizeVarName()
			if err != nil {
				return nil, err
			}

			var c *parser.ColumnItem
			switch t := v.(type) {
			case *parser.ColumnItem:
				c = t
			default:
				return nil, fmt.Errorf("invalid syntax for ORDER BY: %s", v)
			}

			if c.TableName.Table() == "" {
				// Look for an output column that matches the name. This
				// handles cases like:
				//
				//   SELECT a AS b FROM t ORDER BY b
				target := sqlbase.NormalizeName(c.ColumnName)
				for j, col := range columns {
					if sqlbase.ReNormalizeName(col.Name) == target {
						index = j
						break
					}
				}
			}

			if s, ok := n.(*selectNode); ok && index == -1 {
				// No output column matched the  name, so look for an existing
				// render target that matches the column name. This handles cases like:
				//
				//   SELECT a AS b FROM t ORDER BY a
				colIdx, err := s.source.findUnaliasedColumn(c)
				if err != nil {
					return nil, err
				}
				if colIdx != invalidColIdx {
					for j, r := range s.render {
						if qval, ok := r.(*qvalue); ok {
							if qval.colRef.source == s.source.info && qval.colRef.colIdx == colIdx {
								index = j
								break
							}
						}
					}
				}
			}
		}

		if index == -1 {
			// The order by expression matched neither an output column nor an
			// existing render target.
			if col, err := colIndex(numOriginalCols, expr); err != nil {
				return nil, err
			} else if col >= 0 {
				index = col
			} else if s, ok := n.(*selectNode); ok {
				// TODO(dan): Once we support VALUES (1), (2) ORDER BY 3*4, this type
				// check goes away.

				// Add a new render expression to use for ordering. This
				// handles cases were the expression is either not a name or
				// is a name that is otherwise not referenced by the query:
				//
				//   SELECT a FROM t ORDER by b
				//   SELECT a, b FROM t ORDER by a+b
				if err := s.addRender(parser.SelectExpr{Expr: expr}, nil); err != nil {
					return nil, err
				}
				index = len(s.columns) - 1
			} else {
				return nil, errors.Errorf("column %s does not exist", expr)
			}
		}
		direction := encoding.Ascending
		if o.Direction == parser.Descending {
			direction = encoding.Descending
		}
		ordering = append(ordering, sqlbase.ColumnOrderInfo{ColIdx: index, Direction: direction})
	}

	return &sortNode{ctx: p.ctx(), columns: columns, ordering: ordering}, nil
}
Esempio n. 10
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// getTableLease implements the SchemaAccessor interface.
func (p *planner) getTableLease(tn *parser.TableName) (*sqlbase.TableDescriptor, error) {
	if log.V(2) {
		log.Infof(p.ctx(), "planner acquiring lease on table %s", tn)
	}

	isSystemDB := tn.Database() == sqlbase.SystemDB.Name
	isVirtualDB := isVirtualDatabase(tn.Database())
	if isSystemDB || isVirtualDB || testDisableTableLeases {
		// We don't go through the normal lease mechanism for:
		// - system tables. The system.lease and system.descriptor table, in
		//   particular, are problematic because they are used for acquiring
		//   leases itself, creating a chicken&egg problem.
		// - virtual tables. These tables' descriptors are not persisted,
		//   so they cannot be leased. Instead, we simply return the static
		//   descriptor and rely on the immutability privileges set on the
		//   descriptors to cause upper layers to reject mutations statements.
		tbl, err := p.mustGetTableDesc(tn)
		if err != nil {
			return nil, err
		}
		if err := filterTableState(tbl); err != nil {
			return nil, err
		}
		return tbl, nil
	}

	dbID, err := p.getDatabaseID(tn.Database())
	if err != nil {
		return nil, err
	}

	// First, look to see if we already have a lease for this table.
	// This ensures that, once a SQL transaction resolved name N to id X, it will
	// continue to use N to refer to X even if N is renamed during the
	// transaction.
	var lease *LeaseState
	for _, l := range p.leases {
		if sqlbase.ReNormalizeName(l.Name) == sqlbase.NormalizeName(tn.TableName) &&
			l.ParentID == dbID {
			lease = l
			if log.V(2) {
				log.Infof(p.ctx(), "found lease in planner cache for table %q", tn)
			}
			break
		}
	}

	// If we didn't find a lease or the lease is about to expire, acquire one.
	if lease == nil || p.removeLeaseIfExpiring(lease) {
		var err error
		lease, err = p.leaseMgr.AcquireByName(p.txn, dbID, tn.Table())
		if err != nil {
			if err == sqlbase.ErrDescriptorNotFound {
				// Transform the descriptor error into an error that references the
				// table's name.
				return nil, sqlbase.NewUndefinedTableError(tn.String())
			}
			return nil, err
		}
		p.leases = append(p.leases, lease)
		// If the lease we just acquired expires before the txn's deadline, reduce
		// the deadline.
		p.txn.UpdateDeadlineMaybe(hlc.Timestamp{WallTime: lease.Expiration().UnixNano()})
	}
	return &lease.TableDescriptor, nil
}
Esempio n. 11
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func (p *planner) makeUpsertHelper(
	tn *parser.TableName,
	tableDesc *sqlbase.TableDescriptor,
	insertCols []sqlbase.ColumnDescriptor,
	updateCols []sqlbase.ColumnDescriptor,
	updateExprs parser.UpdateExprs,
	upsertConflictIndex *sqlbase.IndexDescriptor,
) (*upsertHelper, error) {
	defaultExprs, err := makeDefaultExprs(updateCols, &p.parser, &p.evalCtx)
	if err != nil {
		return nil, err
	}

	untupledExprs := make(parser.Exprs, 0, len(updateExprs))
	i := 0
	for _, updateExpr := range updateExprs {
		if updateExpr.Tuple {
			if t, ok := updateExpr.Expr.(*parser.Tuple); ok {
				for _, e := range t.Exprs {
					typ := updateCols[i].Type.ToDatumType()
					e := fillDefault(e, typ, i, defaultExprs)
					untupledExprs = append(untupledExprs, e)
					i++
				}
			}
		} else {
			typ := updateCols[i].Type.ToDatumType()
			e := fillDefault(updateExpr.Expr, typ, i, defaultExprs)
			untupledExprs = append(untupledExprs, e)
			i++
		}
	}

	sourceInfo := newSourceInfoForSingleTable(*tn, makeResultColumns(tableDesc.Columns))
	excludedSourceInfo := newSourceInfoForSingleTable(upsertExcludedTable, makeResultColumns(insertCols))

	var evalExprs []parser.TypedExpr
	qvals := make(qvalMap)
	sources := multiSourceInfo{sourceInfo, excludedSourceInfo}
	for _, expr := range untupledExprs {
		normExpr, err := p.analyzeExpr(expr, sources, qvals, parser.NoTypePreference, false, "")
		if err != nil {
			return nil, err
		}
		evalExprs = append(evalExprs, normExpr)
	}

	allExprsIdentity := true
	for i, expr := range evalExprs {
		// analyzeExpr above has normalized all direct column names to ColumnItems.
		c, ok := expr.(*parser.ColumnItem)
		if !ok {
			allExprsIdentity = false
			break
		}
		if len(c.Selector) > 0 ||
			!sqlbase.EqualName(c.TableName.TableName, upsertExcludedTable.TableName) ||
			sqlbase.NormalizeName(c.ColumnName) != sqlbase.ReNormalizeName(updateCols[i].Name) {
			allExprsIdentity = false
			break
		}
	}

	helper := &upsertHelper{
		p:                  p,
		qvals:              qvals,
		evalExprs:          evalExprs,
		sourceInfo:         sourceInfo,
		excludedSourceInfo: excludedSourceInfo,
		allExprsIdentity:   allExprsIdentity,
	}

	return helper, nil
}